DNA damage, cancer caused by ionizing radiation identified

This UPI article was published on Sept. 13, 2016.
I added below the source of that UPI article, the study published on the sciences website “Nature” on Sept. 12, 2016.
This article is important, and should be seen by as many people as possible, as this scientific study will impact greatly the future of our anti-nuclear cause.
By establishing the genetic signatures of any cancer caused by ionizing radiation, any future denial from the nuclear lobby is now impossible. Those scientifically established signatures will also be extremely helpful in court for any future suit from radiation victims.

Researchers found mutational signatures left by radiation-caused changes to DNA, which may lead to better treatment of cancers.

dna-damage-cancer-caused-by-ionizing-radiation-identified

Researchers found mutational signatures which appear to indicate changes to DNA caused by exposure to ionizing radiation, which may allow doctors to better treat cancer caused by non-spontaneous mutations.

LONDON, Sept. 13 (UPI) — Though scientists have suspected ionizing radiation can cause cancer, experiments conducted in England are the first to show the damage it inflicts on DNA and may allow doctors to identify tumors caused by radiation.

In a study published in the journal Nature Communications, scientists showed the effects of gamma rays, X-rays and radioactive particles on DNA, deciphering patterns they think will help differentiate between spontaneous and radiation-caused tumors, allowing for better cancer treatment.

“To find out how radiation could cause cancer, we studied the genomes of cancers caused by radiation in comparison to tumors that arose spontaneously,” Dr. Peter Campbell, a researchers at the Wellcome Trust Sanger Institute, said in a press release. “By comparing the DNA sequences we found two mutational signatures for radiation damage that were independent of cancer type. We then checked the findings with prostate cancers that had or had not been exposed to radiation, and found the same two signatures again. These mutational signatures help us explain how high-energy radiation damages DNA.”

For the study, the researchers looked for mutational signatures in 12 cancer patients with radiation-associated second malignancies, and compared their tumors to 319 from patients not exposed to radiation.

The researchers found two mutational signatures they link to radiation. While one causes small deletions of DNA bases, the other — called a balanced inversion — includes two cuts to DNA, with the middle piece spinning around and rejoining in the opposite direction.

These mutations, especially balanced inversions, which do not happen naturally in the body, increase the potential for cancer to develop, the researchers say.

“This is the first time that scientists have been able to define the damage caused to DNA by ionising radiation,” said Adrienne Flanagan, a professor at the University College London Cancer Institute. “These mutational signatures could be a diagnosis tool for both individual cases, and for groups of cancers, and could help us find out which cancers are caused by radiation. Once we have better understanding of this, we can study whether they should be treated the same or differently to other cancers.”

http://www.upi.com/Health_News/2016/09/13/DNA-damage-cancer-caused-by-ionizing-radiation-identified/5151473765849/

Mutational signatures of ionizing radiation in second malignancies

« Ionizing radiation is a potent carcinogen, inducing cancer through DNA damage. The signatures of mutations arising in human tissues following in vivo exposure to ionizing radiation have not been documented. Here, we searched for signatures of ionizing radiation in 12 radiation-associated second malignancies of different tumour types. Two signatures of somatic mutation characterize ionizing radiation exposure irrespective of tumour type. Compared with 319 radiation-naive tumours, radiation-associated tumours carry a median extra 201 deletions genome-wide, sized 1–100 base pairs often with microhomology at the junction. Unlike deletions of radiation-naive tumours, these show no variation in density across the genome or correlation with sequence context, replication timing or chromatin structure. Furthermore, we observe a significant increase in balanced inversions in radiation-associated tumours. Both small deletions and inversions generate driver mutations. Thus, ionizing radiation generates distinctive mutational signatures that explain its carcinogenic potential. »

http://www.nature.com/ncomms/2016/160907/ncomms12605/full/ncomms12605.html